cant understand..air pollution

shipra · Posted: Wed Jul 02, 2008 3:39 am Post subject: cant understand..air pollution

2. In the years since the city of London imposed strict air-pollution regulations on local industry, the number of bird species seen in and around London has increased dramatically. Similar air-pollution rules should be imposed in other major cities.
Each of the following is an assumption made in the argument above EXCEPT:
(A) In most major cities, air-pollution problems are caused almost entirely by local industry.
(B) Air-pollution regulations on industry have a significant impact on the quality of the air.
(C) The air-pollution problems of other major cities are basically similar to those once suffered by London.
(D) An increase in the number of bird species in and around a city is desirable.
(E) The increased sightings of bird species in and around London reflect an actual increase in the number of species in the area.

raunekk · Posted: Wed Jul 02, 2008 4:34 am Post subject:

is d answer E??

raviagni · Posted: Wed Jul 02, 2008 8:28 am Post subject:

I find B as the OA

The quality of air is not the assumption

what's the OA?

raunekk · Posted: Wed Jul 02, 2008 9:44 am Post subject:

a doubt..

doesnt air pollution signify quality of air??

chidcguy · Posted: Wed Jul 02, 2008 10:51 am Post subject:

(A) In most major cities, air-pollution problems are caused almost entirely by local industry.

What if AP problems are not caused by local industry? no need to impose regulations and conclusion falls apart

(B) Air-pollution regulations on industry have a significant impact on the quality of the air.

What if AP regulations do not have an impact on the air quality? no need to impose regulations and conclusion falls apart

(C) The air-pollution problems of other major cities are basically similar to those once suffered by London.

What if the AP problems of other cities are not similar? No need to impose same regulations and conclusion falls apart

(D) An increase in the number of bird species in and around a city is desirable.

What if the increase in number of bird species is NOT desired in London or other cities? It is still possible that the AP can be reduced.

(E) The increased sightings of bird species in and around London reflect an actual increase in the number of species in the area.

What if the increased sightings do not reflect actual increase? London did not reduce AP by regulating local industry. No need for other cities to emulate.

To me, the negation test pulled the conclusion apart except in D

Hence my pick is D. What is OA?

raunekk · Posted: Wed Jul 02, 2008 11:24 am Post subject:

i was confused between D and E...but then choose E!!(this always happens with me

)

Its still not clear..even i tried the negation rule !!But then ...if the Birds population is not desirable then whats the point in taking steps to prevent AP???

But after chidcguys explanation ..i think E is a stronger contender

thx

Carlo75 · Posted: Wed Jul 02, 2008 12:03 pm Post subject:

I will go with A.

air-pollution problems are caused almost entirely by local industry, the word entirely is too extreme to be an assumption ...

But I have still doubts

chidcguy · Posted: Wed Jul 02, 2008 12:20 pm Post subject:

Another reason why D is my pick is

Assumption and conclusion are close to each other. D does not even talk about the regulations or the AP reduction that resulted from those regulations on local industry. bird increase is just evidence thats not the goal.

With E, its saying that the evidence was misinterpreted. If the evidence was misinterpreted then the AP actually did not go down. If AP did not go down, why should other cities follow same sort of regulations? For the conclusion to stay intact the evidence should correspond to an actual increase and AP reduction.

Ian Stewart · Posted: Wed Jul 02, 2008 12:49 pm Post subject:

In the years since the city of London imposed strict air-pollution regulations on local industry, the number of bird species seen in and around London has increased dramatically. Similar air-pollution rules should be imposed in other major cities.
Each of the following is an assumption made in the argument above EXCEPT:

Often the words in CR questions encourage us to bring outside knowledge to the question. We might think, when reading the above, 'of course air pollution is bad, and should be reduced', and this might lead us to ignore the structure of the argument. The argument says, essentially, "London imposed air pollution laws. The number of birds went up. Therefore the rules should be applied everywhere."

When I see an argument like this, I'll normally replace, in my head, the words with letters. The argument is: "London did X. The number of Y went up. Therefore every other city should do X." Now the argument's structure is clear; the fact that Y went up is the justification for implementing X.

In the original argument, what is the justification for the conclusion? Precisely that there were more birds. It's an unstated assumption that having more birds is a good thing; it's the only justification for improving air quality that is provided. So D is one of the assumptions. That we should apply London's rules elsewhere assumes other cities are similar: C is an assumption. That the increased sightings of birds actually represents an increase in the number of birds is another assumption: E is also assumed.

B is not an assumption explicitly made in the argument. I suppose it's possible that air pollution regulations led to more birds for a different reason than by improving air quality, but that seems far-fetched. Still, if no other answer were good, this would be the choice. A, however, is clearly not assumed in the argument. The argument does not assume that local industry is 'almost entirely' the source of air pollution. It only assumes that regulation on local industry will have a positive effect.

Incidentally, there aren't many birds in London!

______________

(A) In most major cities, air-pollution problems are caused almost entirely by local industry.
(B) Air-pollution regulations on industry have a significant impact on the quality of the air.
(C) The air-pollution problems of other major cities are basically similar to those once suffered by London.
(D) An increase in the number of bird species in and around a city is desirable.
(E) The increased sightings of bird species in and around London reflect an actual increase in the number of species in the area.

bigfernhead · Posted: Thu Jul 17, 2008 12:05 pm Post subject:

I see your point of A).

However, I went with D).

I couldn't assume from the passage that more birds = more desirable.

Good example: Pigeons. Can't imagine having more of them is a good thing Wink

What's the OA?

kiranlegend · Posted: Thu Jul 17, 2008 8:51 pm Post subject:

mate, the OA is given as A

NSNguyen · Posted: Fri Jul 18, 2008 7:48 am Post subject:

I would go with E when it is out of scope.
Laughing